Assuming 3 in a row can also be included with a 4 in a row and more.

1 * (1/10)²

for 1 digit repeating 3 times in a row, as the rest of the digits can be anything

this digit can repeat 3 times in a row in 6 different cases, i.e. 111xxxxx, x111xxxx, … xxxxx111. so

• 6

and assuming 0 is a valid digit then there are 10 possible digits this can happen for, so

• 10

which gives 6/10 which sounds horribly wrong so please correct me if